东湖水库强风暴雨遭遇联合分布及其对坝顶高程设计的影响  

Joint distribution of strong wind and rainstorm in Donghu Reservoir and its impact on the design of dam crest elevation

作　　者：蔡奇霖 涂金良 王兆礼[1] 赖成光[1] CAI Qilin;TU Jinliang;WANG Zhaoli;LAI Chengguang(School of Civil Engineering&Transportation,South China University of Technology,Guangzhou 510640,China;Guangdong Technology Center of Water Resources and Hydropower,Guangzhou 510635,China)

机构地区：[1]华南理工大学土木与交通学院,广东广州510640 [2]广东省水利水电技术中心,广东广州510635

出　　处：《水资源与水工程学报》2022年第1期117-123,129,共8页Journal of Water Resources and Water Engineering

基　　金：国家自然科学基金项目(51709117);广东省水利科技创新项目(2020-28)。

摘　　要：为探讨强风暴雨遭遇的联合分布及其对坝顶高程设计的影响,以东湖水库为研究对象,利用广义极值分布(GEV)、伽马分布(Gamma)和皮尔逊Ⅲ型分布(P-Ⅲ)分别对最大风速和3组降雨序列进行边缘分布拟合,基于二元Copula函数构造最大风速和降雨序列的联合概率分布,估算100年一遇重现期下风速和降雨设计值,并复核水库主坝坝顶高程是否满足安全要求。结果表明:东湖水库年最大日降雨量呈显著增大趋势(P<0.05),年最大风速则呈现不显著增大趋势,且历史上出现过年最大风速遭遇年最大暴雨的情景;对于遭遇分析,无论是最大风速还是暴雨的计算值均呈现“联合重现期>单变量重现期>同现重现期”的规律,其中联合重现期最大风速值比仅考虑单变量的最大风速值大10%左右;基于联合重现期最大风速所推算的坝顶高程低于大坝防浪墙的实际高程,表明大坝高程能满足100年一遇强风暴雨遭遇的安全要求。研究成果可为我国沿海地区水库大坝的设计风速计算和坝顶高程设计提供参考依据。The main objective of this study is to discuss the joint distribution of strong wind and rainstorm and its impacts on the design value of dam crest elevation.Taking Donghu Reservoir as the study object,we conducted marginal distribution fitting between maximum wind speed and three sets of rainfall series using GEV,Gamma,and P-Ⅲ distribution respectively.Based on the joint probability distribution of maximum wind speed and rainfall series constructed by the binary Copula functions,the design values of wind speed and rainstorm of 100-year return period were estimated and the crest elevation of the main dam was re-checked whether it met the safety requirements.The results show that the annual maximum daily rainfall presented a significant upward trend(P<0.05),whereas the annual maximum wind speed featured a non-significant one,and the maximum rainfall event once occurred at the same time with the maximum wind event.As for the encounter analysis,both the calculated values of maximum wind speed and rainfall showed a rule as“joint return period>univariate return period>co-occurrence return period”,of which the value of maximum wind speed of joint return period was only approximately 10% larger than that of univariate return period.The estimated value of crest elevation based on joint return period was lower than the actual value of the wave wall,indicating that the crest elevation of the main dam could meet the safety requirements of the encounter of strong wind and rainstorm(100-yr).The results of this study can provide references for the calculation of design wind speed and crest elevation of reservoir dams in the coastal regions of China.

关 键 词：强风 暴雨 遭遇分析 坝顶高程设计 COPULA函数 东湖水库 

分 类 号：TV622[水利工程—水利水电工程]